The discovery of denitrifying anaerobic methane oxidation (DAMO) enables the complete N removal from wastewater by utilizing the methane produced onsite from anaerobic digesters. This model-based study evaluates complete nitrogen removal by coupling nitritation-Anammox and DAMO in membrane biofilm reactors (MBfRs). The influences of nitritation produced NO2/NH4 ratio, methane supply and total n...

Ammonia is one of the most important contaminants impairing the quality of water resources. When this is considered along with the fact that the global demand for nitrogenous fertilizers is in constant rise, the need for recovery as well as removal of nitrogen is well justified. Crystallization of N and P in the form of struvite (MgNH4PO4 6H2O), which is a slow releasing and valuable fertilizer...

Streams alter the concentration of nutrients they transport and thereby influence nutrient loading to estuaries downstream; however, the relationship between in-stream uptake, discharge variability, and subsequent nutrient export is poorly understood. In this study, in-stream N and P uptake were examined in the stream network draining a row-crop agricultural operation in coastal North Carolina....

Shewanella loihica strain PV-4 harbors both a functional denitrification (NO3 (-)→N2) and a respiratory ammonification (NO3 (-)→NH4 (+)) pathway. Batch and chemostat experiments revealed that NO2 (-) affects pathway selection and the formation of reduced products. Strain PV-4 cells grown with NO2 (-) as the sole electron acceptor produced exclusively NH4 (+). With NO3 (-) as the electron accept...

The principal initial product of metabolism of 13N-labeled ammonium by Anabaena cylindrica grown with either NH4+ or N2 as nitrogen source is amide-labeled glutamine. The specific activity of glutamine synthetase is approximately half as great in NH4+-grown as in N2-grown filaments. After 1.5 min of exposure to 13NH4+, the ratio of 13N in glutamate to 13N in glutamine reaches a value of approxi...

Each year, millions of hatchery-raised fish are stocked into streams and rivers worldwide, yet the effects of hatchery-raised fish on stream nutrient cycles have seldom been examined. We quantified the influence of supplemental nonnative fish stocking, a widespread recreational fishery management practice, on in-stream nutrient storage and cycling. We predicted that supplemental, hatchery-raise...

Pig manure is an excellent fertilizer and rich source of organic carbon and nitrogen compounds such organic nitrogen (O-N) (95% of total nitrogen) that is plant-unavailable-nitrogen (PUN) and mineralized nitrogen (about 1% of total nitrogen) such as ammonium (NH4+) and nitrate (NO3) that are plant-available-nitrogen (PAN). In addition, manure also contains two forms of estrogens: (i) poorly est...

The objective of this study was to investigate the feasibility of using Near-Infrared Spectroscopy (NIRS) to determine the total nitrogen, ammonium and nitrate nitrogen in growing substrates of vinegar residues. Samples of 106 substrates were collected from the cultivation experiments of vinegar residue substrates. Spectra of the visible and near infrared region (350-2500 nm) were obtained for ...